view tests/test-rebase-cache.t @ 42743:8c9a6adec67a

rust-discovery: using the children cache in add_missing

The DAG range computation often needs to get back to very old
revisions, and turns out to be disproportionately long, given
that the end goal is to remove the descendents of the given
missing revisons from the undecided set.

The fast iteration capabilities available in the Rust case make
it possible to avoid the DAG range entirely, at the cost of
precomputing the children cache, and to simply iterate on
children of the given missing revisions.

This is a case where staying on the same side of the interface
between the two languages has clear benefits.

On discoveries with initial undecided sets
small enough to bypass sampling entirely, the total cost of
computing the children cache and the subsequent iteration
becomes better than the Python + C counterpart, which relies on
reachableroots2.

For example, on a repo with more than one million revisions with
an initial undecided set of 11 elements, we get these figures:

Rust version with simple iteration
  addcommons: 57.287us
  first undecided computation: 184.278334ms
  first children cache computation: 131.056us
  addmissings iteration: 42.766us
  first addinfo total: 185.24 ms

Python + C version
  first addcommons: 0.29 ms
  addcommons 0.21 ms
  first undecided computation 191.35 ms
  addmissings 45.75 ms
  first addinfo total: 237.77 ms

On discoveries with large undecided sets, the initial price paid
makes the first addinfo slower than the Python + C version,
but that's more than compensated by the gain in sampling and
subsequent iterations.
Here's an extreme example with an undecided set of a million revisions:

Rust version:
  first undecided computation: 293.842629ms
  first children cache computation: 407.911297ms
  addmissings iteration: 34.312869ms
  first addinfo total: 776.02 ms
  taking initial sample
  query 2: sampling time: 1318.38 ms
  query 2; still undecided: 1005013, sample size is: 200
  addmissings: 143.062us

Python + C version:
  first undecided computation 298.13 ms
  addmissings 80.13 ms
  first addinfo total: 399.62 ms
  taking initial sample
  query 2: sampling time: 3957.23 ms
  query 2; still undecided: 1005013, sample size is: 200
  addmissings 52.88 ms

Differential Revision: https://phab.mercurial-scm.org/D6428

  $ cat >> $HGRCPATH <<EOF
  > [extensions]
  > rebase=
  > mq=
  > 
  > [phases]
  > publish=False
  > 
  > [alias]
  > tglog  = log -G --template "{rev}: '{desc}' {branches}\n"
  > theads = heads --template "{rev}: '{desc}' {branches}\n"
  > EOF

  $ hg init a
  $ cd a

  $ echo a > a
  $ hg ci -Am A
  adding a

  $ hg branch branch1
  marked working directory as branch branch1
  (branches are permanent and global, did you want a bookmark?)
  $ hg ci -m 'branch1'

  $ echo b > b
  $ hg ci -Am B
  adding b

  $ hg up -q 0

  $ hg branch branch2
  marked working directory as branch branch2
  $ hg ci -m 'branch2'

  $ echo c > C
  $ hg ci -Am C
  adding C

  $ hg up -q 2

  $ hg branch -f branch2
  marked working directory as branch branch2
  $ echo d > d
  $ hg ci -Am D
  adding d
  created new head

  $ echo e > e
  $ hg ci -Am E
  adding e

  $ hg update default
  0 files updated, 0 files merged, 3 files removed, 0 files unresolved

  $ hg branch branch3
  marked working directory as branch branch3
  $ hg ci -m 'branch3'

  $ echo f > f
  $ hg ci -Am F
  adding f

  $ cd ..


Rebase part of branch2 (5-6) onto branch3 (8):

  $ hg clone -q -u . a a1
  $ cd a1

  $ hg tglog
  @  8: 'F' branch3
  |
  o  7: 'branch3' branch3
  |
  | o  6: 'E' branch2
  | |
  | o  5: 'D' branch2
  | |
  | | o  4: 'C' branch2
  | | |
  +---o  3: 'branch2' branch2
  | |
  | o  2: 'B' branch1
  | |
  | o  1: 'branch1' branch1
  |/
  o  0: 'A'
  
  $ hg branches
  branch3                        8:4666b71e8e32
  branch2                        6:5097051d331d
  branch1                        2:0a03079c47fd (inactive)
  default                        0:1994f17a630e (inactive)

  $ hg theads
  8: 'F' branch3
  6: 'E' branch2
  4: 'C' branch2
  2: 'B' branch1
  0: 'A' 

  $ hg rebase -s 5 -d 8
  rebasing 5:635859577d0b "D"
  rebasing 6:5097051d331d "E"
  saved backup bundle to $TESTTMP/a1/.hg/strip-backup/635859577d0b-89160bff-rebase.hg

  $ hg branches
  branch3                        8:466cdfb14b62
  branch2                        4:e4fdb121d036
  branch1                        2:0a03079c47fd
  default                        0:1994f17a630e (inactive)

  $ hg theads
  8: 'E' branch3
  4: 'C' branch2
  2: 'B' branch1
  0: 'A' 

  $ hg tglog
  o  8: 'E' branch3
  |
  o  7: 'D' branch3
  |
  @  6: 'F' branch3
  |
  o  5: 'branch3' branch3
  |
  | o  4: 'C' branch2
  | |
  | o  3: 'branch2' branch2
  |/
  | o  2: 'B' branch1
  | |
  | o  1: 'branch1' branch1
  |/
  o  0: 'A'
  
  $ cd ..


Rebase head of branch3 (8) onto branch2 (6):

  $ hg clone -q -u . a a2
  $ cd a2

  $ hg tglog
  @  8: 'F' branch3
  |
  o  7: 'branch3' branch3
  |
  | o  6: 'E' branch2
  | |
  | o  5: 'D' branch2
  | |
  | | o  4: 'C' branch2
  | | |
  +---o  3: 'branch2' branch2
  | |
  | o  2: 'B' branch1
  | |
  | o  1: 'branch1' branch1
  |/
  o  0: 'A'
  
  $ hg rebase -s 8 -d 6
  rebasing 8:4666b71e8e32 "F" (tip)
  saved backup bundle to $TESTTMP/a2/.hg/strip-backup/4666b71e8e32-fc1c4e96-rebase.hg

  $ hg branches
  branch2                        8:6b4bdc1b5ac0
  branch3                        7:653b9feb4616
  branch1                        2:0a03079c47fd (inactive)
  default                        0:1994f17a630e (inactive)

  $ hg theads
  8: 'F' branch2
  7: 'branch3' branch3
  4: 'C' branch2
  2: 'B' branch1
  0: 'A' 

  $ hg tglog
  @  8: 'F' branch2
  |
  | o  7: 'branch3' branch3
  | |
  o |  6: 'E' branch2
  | |
  o |  5: 'D' branch2
  | |
  | | o  4: 'C' branch2
  | | |
  | | o  3: 'branch2' branch2
  | |/
  o |  2: 'B' branch1
  | |
  o |  1: 'branch1' branch1
  |/
  o  0: 'A'
  
  $ hg verify -q

  $ cd ..


Rebase entire branch3 (7-8) onto branch2 (6):

  $ hg clone -q -u . a a3
  $ cd a3

  $ hg tglog
  @  8: 'F' branch3
  |
  o  7: 'branch3' branch3
  |
  | o  6: 'E' branch2
  | |
  | o  5: 'D' branch2
  | |
  | | o  4: 'C' branch2
  | | |
  +---o  3: 'branch2' branch2
  | |
  | o  2: 'B' branch1
  | |
  | o  1: 'branch1' branch1
  |/
  o  0: 'A'
  
  $ hg rebase -s 7 -d 6
  rebasing 7:653b9feb4616 "branch3"
  note: not rebasing 7:653b9feb4616 "branch3", its destination already has all its changes
  rebasing 8:4666b71e8e32 "F" (tip)
  saved backup bundle to $TESTTMP/a3/.hg/strip-backup/653b9feb4616-3c88de16-rebase.hg

  $ hg branches
  branch2                        7:6b4bdc1b5ac0
  branch1                        2:0a03079c47fd (inactive)
  default                        0:1994f17a630e (inactive)

  $ hg theads
  7: 'F' branch2
  4: 'C' branch2
  2: 'B' branch1
  0: 'A' 

  $ hg tglog
  @  7: 'F' branch2
  |
  o  6: 'E' branch2
  |
  o  5: 'D' branch2
  |
  | o  4: 'C' branch2
  | |
  | o  3: 'branch2' branch2
  | |
  o |  2: 'B' branch1
  | |
  o |  1: 'branch1' branch1
  |/
  o  0: 'A'
  
  $ hg verify -q

Stripping multiple branches in one go bypasses the fast-case code to
update the branch cache.

  $ hg strip 2
  0 files updated, 0 files merged, 4 files removed, 0 files unresolved
  saved backup bundle to $TESTTMP/a3/.hg/strip-backup/0a03079c47fd-11b7c407-backup.hg

  $ hg tglog
  o  3: 'C' branch2
  |
  o  2: 'branch2' branch2
  |
  | @  1: 'branch1' branch1
  |/
  o  0: 'A'
  

  $ hg branches
  branch2                        3:e4fdb121d036
  branch1                        1:63379ac49655
  default                        0:1994f17a630e (inactive)

  $ hg theads
  3: 'C' branch2
  1: 'branch1' branch1
  0: 'A' 

Fast path branchcache code should not be invoked if branches stripped is not
the same as branches remaining.

  $ hg init b
  $ cd b

  $ hg branch branch1
  marked working directory as branch branch1
  (branches are permanent and global, did you want a bookmark?)
  $ hg ci -m 'branch1'

  $ hg branch branch2
  marked working directory as branch branch2
  $ hg ci -m 'branch2'

  $ hg branch -f branch1
  marked working directory as branch branch1

  $ echo a > A
  $ hg ci -Am A
  adding A
  created new head

  $ hg tglog
  @  2: 'A' branch1
  |
  o  1: 'branch2' branch2
  |
  o  0: 'branch1' branch1
  

  $ hg theads
  2: 'A' branch1
  1: 'branch2' branch2

  $ hg strip 2
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  saved backup bundle to $TESTTMP/a3/b/.hg/strip-backup/a5b4b27ed7b4-a3b6984e-backup.hg

  $ hg theads
  1: 'branch2' branch2
  0: 'branch1' branch1


Make sure requesting to strip a revision already stripped does not confuse things.
Try both orders.

  $ cd ..

  $ hg init c
  $ cd c

  $ echo a > a
  $ hg ci -Am A
  adding a
  $ echo b > b
  $ hg ci -Am B
  adding b
  $ echo c > c
  $ hg ci -Am C
  adding c
  $ echo d > d
  $ hg ci -Am D
  adding d
  $ echo e > e
  $ hg ci -Am E
  adding e

  $ hg tglog
  @  4: 'E'
  |
  o  3: 'D'
  |
  o  2: 'C'
  |
  o  1: 'B'
  |
  o  0: 'A'
  

  $ hg strip 3 4
  0 files updated, 0 files merged, 2 files removed, 0 files unresolved
  saved backup bundle to $TESTTMP/a3/c/.hg/strip-backup/67a385d4e6f2-b9243789-backup.hg

  $ hg theads
  2: 'C' 

  $ hg strip 2 1
  0 files updated, 0 files merged, 2 files removed, 0 files unresolved
  saved backup bundle to $TESTTMP/a3/c/.hg/strip-backup/6c81ed0049f8-a687065f-backup.hg

  $ hg theads
  0: 'A' 

Make sure rebase does not break for phase/filter related reason
----------------------------------------------------------------
(issue3858)

  $ cd ..

  $ cat >> $HGRCPATH << EOF
  > [ui]
  > logtemplate={rev} {desc} {phase}\n
  > EOF


  $ hg init c4
  $ cd c4

  $ echo a > a
  $ hg ci -Am A
  adding a
  $ echo b > b
  $ hg ci -Am B
  adding b
  $ hg up 0
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ echo c > c
  $ hg ci -Am C
  adding c
  created new head
  $ hg up 1
  1 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ hg merge
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  $ hg ci -m d
  $ hg up 2
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ echo e > e
  $ hg ci -Am E
  adding e
  created new head
  $ hg merge 3
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  $ hg ci -m F
  $ hg up 3
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ echo g > g
  $ hg ci -Am G
  adding g
  created new head
  $ echo h > h
  $ hg ci -Am H
  adding h
  $ hg up 5
  1 files updated, 0 files merged, 2 files removed, 0 files unresolved
  $ echo i > i
  $ hg ci -Am I
  adding i

Turn most changeset public

  $ hg ph -p 7

  $ hg heads
  8 I draft
  7 H public
  $ hg log -G
  @  8 I draft
  |
  | o  7 H public
  | |
  | o  6 G public
  | |
  o |  5 F draft
  |\|
  o |  4 E draft
  | |
  | o  3 d public
  |/|
  o |  2 C public
  | |
  | o  1 B public
  |/
  o  0 A public
  

  $ cat > $TESTTMP/checkeditform.sh <<EOF
  > env | grep HGEDITFORM
  > true
  > EOF
  $ HGEDITOR="sh $TESTTMP/checkeditform.sh" hg rebase --dest 7 --source 5 -e
  rebasing 5:361a99976cc9 "F"
  HGEDITFORM=rebase.merge
  rebasing 8:326cfedc031c "I" (tip)
  HGEDITFORM=rebase.normal
  saved backup bundle to $TESTTMP/a3/c4/.hg/strip-backup/361a99976cc9-35e980d0-rebase.hg